four bolts stick out on new 300D alternator - should I whack them off?
 

You might have trouble returning it to NAPA if you cut the bolts off.

Yes no return if tamperd with.Also thats not right ,bolts dont srick out of new lifetime alternators . Dont understand this,, something isnot right.

The bolts are threaded , and the alternator case is also . The bolts should be flush to the aternator case.The bolts should not stick out .The service centre was short of the right length bolts and put a one size in .Take it back and get them to sort it out.Not your job to ,as its wrong. Look like a china job.

Before leaving the building it is a good idea to ask them to test the Alternator for you even if it is a rebuilt one.

Re-confirming it is a good before you install it can help you troubleshoot if after the installation you are still not charging.

Looks like those bolts are for the shield.

Since its warrantied, bring it back. If it wasn't, my suggestion would be to take out all four bolts, and either trim them or replace them, but not to cut them in place. At the same time, you could rotate the case to the correct clocking.

I replaced the nearly seized factory alternator on my Mazda with a rebuild a few years ago and the first rebuild I had put out like 20 volts from the first time it was started. It caused my dash lights to be extremely bright, so I knew right away something was wrong. It blew both my fog lights but thankfully nothing else electric was damaged.

Had to take it back to the store and they tested it and their test said it was ok. Ended up swapping in the broken alt again to make sure it wasn't my car, had to bring rebuild alt back to the store a second time and talk to the manager for a long time before he exchanged it and then put that one in.

So ended up having to remove and install an alternator three times, and it's an absolute pain in the arse job on the Mazda. This second alt has been holding up but it makes a high pitched whining noise (not the belt) whenever I use a bunch of electricity (head lights and rear defogger for example)

TL;DR
Rebuild alts suck and don't trust the store test. Don't cut the bolts on the one you have: with rebuilds it's an almost absolute guarantee you WILL have to use that "life time warranty" at least once, so make sure the unit stays in a returnable condition. Rebuilds are much, much cheaper than factory units and now you know why.:P

Bring it back. It should not be that way.

But if you had to, this ^^^.

Those bolts should be that way. Its not a problem with manufacturing. The bolts are for the 1985 California model that has an extra heat shield that goes on the back of the alternator. This is the superseded part and is currently the only one that's available from the ORIGINAL supplier. Alternators from other suppliers that have the flush length bolts are either old stock or are of their own casting & manufacturing (non-oem).

I'd return it based on this pic alone. The regulator is a cheap, non Bosch unit.
How do I know? An alternator rebuild place gave me one for nothing and it does not look well made. Very different design than Bosch, with parts potted in Epoxy. I'd return it for one with a Bosch regulator.

http://www.peachparts.com/shopforum/...rnator-015.jpg

The back cover (which includes the stator and diode bridge) can be installed in any one of four positions. Since the connector isn't in the right place for the harness, this is fixed by removing the bolts and rotating the case.

My thought. But, on my 85 CA 300D, the bolts aren't that long, w/ maybe just 4 threads for the hex nuts that screw on to stand-off the heat shield, so might be a kludge to the standard alternator bolts. I would think if you cut them shorter, NAPA wouldn't notice or care when returned. The main reason for cutting is so you can better swing a wrench when installing/adjusting. The CA heat shield makes that task more challenging.